Abstract

OBJECTIVE: To identify the clinical features in osteosarcoma and to investigate their influence on the prognosis of children and adolescents presenting this disease. MATERIAL AND METHODS: The records of children and adolescents with osteosarcoma treated by the Bone Tumors Group of the state of Rio Grande do Sul, Brazil, between January 1992 and December 2001 were reviewed. RESULTS: Fifty consecutive patients were included in this study. Mean age at diagnosis was 13 years (3-22); 68% of the patients were males. The primary site of disease was the femur in 50% of the patients, tibia in 30%, pelvis in 4%, humerus in 10%, fibula in 2% and other sites in 4%. Nineteen patients presented metastases at diagnosis (38%). All patients received chemotherapy and were treated with three different schemes. As for surgical treatment, 26 patients (52%) had an amputation and 17 (34%) received conservative surgery. Serum lactic dehydrogenase > 1,000 UI/ml (p = 0.0159, log rank), tumor necrosis < 90% and presence of metastases had a negative influence on prognosis. The overall 5-year survival was of 33.2+7.2% with mean follow-up of 36 months (6-126). Event-free survival was 29.7+7%. The 5-year event-free survival in non-metastatic patients was 45+10.7%, and zero in metastatic patients (follow-up of 78.4 and 18.7 months, respectively). Only two out of 19 metastatic patients are alive and free of disease at 18 and 30 months respectively. CONCLUSION: Metastatic disease at diagnosis, serum levels of serum lactic dehydrogenase > 1,000 UI/ml and tumor necrosis < 90% are predictors of unfavorable prognosis. The excessively high incidence of metastatic patients may suggest the presence of an aggressive pattern of disease in our population, or may indicate late diagnosis.